Ultrahigh voltage metal-oxide-semiconductor (MOS) devices are semiconductor devices that can sustain operation at voltages of several hundred volts, such as, for example, voltages around 600 volts. Among other things, ultrahigh voltage MOS devices are used for level shifters in high-side gate driver circuits. Such a level shifter translates an input signal at a first voltage level to an output signal at a second voltage level to resolve incompatibility between devices that respectively operate at the first and second voltage levels.